Layout protractor



Jan. 4, 1949.

RQ H. s'roRcH LAYOUT PRO'TRACTOR Filed May 16, 1947 Patented Jan. 4, 1949 UNITED STATES PATENT OFFICE y ,2.458,114 t t -LAYOUT PROTItAQTOR Reuben H. Storch, lvlinneapolis, Minn. Application May 16, 1947, `Serial No. `"74`8`,404

4This invention relates to layout protractors particularly adapted for layout work on large flat surfaces. f

It is an object ofemyiinventon to -providea layout protractor for laying off any desired angles onaiat surface.

It is another objectto provide allayout protractor so designed that `the wear between the parts is reduced to a minimum. l l

It is a further object to provide a simple yet highly eicient extremely smoothly operating layoutprotractor having a portion thereof adapted to be securedto thework` and having a rotatable member and means for accurately indicating the angle laid off and for positively locking said rotatable member in any desired position.

These and other objects and advantages of my invention will more fully appear from the following description made in connectionwith lthe accompanying drawings wherein like reference characters refer to similar parts throughout the several views and in which .I

2 Claims. (Cl. 33-75) l Figure 1 is a top plan view of the layout protractor embodying my invention;

Figure 2 is a side elevational tractor shown in Figure 1;

Figure is a transverse vertical sectional view takensubstantially on the line 3-3 of Figure 1; 81nd `1` Y.

Figure 4 is a front end elevational view of the device shown in Figure 1 with the scale removed.

As illustrated in Figures 1 through 4, I provide a layout protractor having a stationary base 5 with an upstanding spindle 6 formed integrally therewith and concentrically disposed thereto, spindle 6 being of lesser diameter than base 5.

A rotatable member 'I having a central bore adapted to receive spindle 6 is jcurnaled on said spindle 6 for 360-degree rotation thereon.

The extreme top of rotatable member 1 has an indicia flange 8 formed thereon and extends concentrically outwardly around the periphery thereof. A S60-degree angular scale 9 is engraved into the top surface adjacent the outer periphery of iew of` the prosaid indicia flange 8.

The center of spindle 6 and base 5 is drilled vout and has a securing pin I 0 passing therethrough. The top portion of spindle 6 is countersunk to receive the head of securing pin I0 and the pin I0 is free to be rotated within the drilled shaft through the spindle 6 and base 5. The lower end of the pin I0 is threaded and is also pointed, adapting it to be secured into a tapped hole in the work, such as the hole II as shown in Figure 3. The head of the pin I0 is slotted so that it may befturned and thus secure the base 5 tightly down uponthe work. l A pointer I2 is secured to the top of spindle "6 as by the screws I3` and has a' central aperture I4 therein which is slightly smaller than the head of the pin I0 but which will permit a tool to be inserted therethrough for turning the pin I0.

At any point intermediate thetop and the bottom of spindle B `a horizontal groove I5 islcut into the verticalcperipheral surface of the spindle E and a `horizontal tapped passage is formed through the side of ,rotatable member 7 and is aligned with the groove I5. A thumb set screw I6 is -threadalcly inserted through said horizontal passage and has its inner end extending into the groove I5. L l

A scale support I1 is fixed to the outer periph.- eryl of said rotatable member l and extends radially outwardly from the zero marking on the angular scale '9. iA. longitudinal slot is cut into the end portion of said support I1 and is adaptable to receive a scale arm I8 as shown in Figures land 2, A set screw `I9 `is provided to securely hold the pointer scale l I8 in its proper radially extendingv position.` The end ofscale support Il is alsotdrilled out longitudinally to receive a rod instead of a scale. Said rod would also be held in place by the set screw |l9. t

The operation of my invention is obvious from the` drawings. `The pointer I2 is initially setat .zveroj on thefvernieryaand the set screw |16 tight- I ened. The Ibase 5 may then be either secured to the work by a tapped hole II and the pin I 0 screwed therein to securely hold said base 5 against the work, or the pointed end of pin I0 may be merely inserted into a center-punched indenture in the work and the base held in place by the operator. The layout scale I8 is then set at the initial terminus of the angle to be laid out. The thumb set screw I6 is then released and any hdesired angle may be laid oi from the initial starting poi-nt, the angle being accurately read on the angular scale 9. The set screw I6 may then be tightened to securely hold the scale I8 in the desired position while the work is marked.

There are two means provided for retaining `the rotatable member l on the spindle 6, one

being the set screw I 6, which even though it is not tightened against the groove I5 may extend a slight distance into said groove I5 and prevent member 1 from. sliding oil the spindle 6; and the other being the pointer I2 with its central disc which holds the central portion of the rotatable membe I onto the spindle 6.

The integral spindle and base construction withl the independently rotatable pin I mounted therethrough provides a simple sationary structure Which may be securely held against the Work and the single rotatable member I journaled on 'said spindle 6 and riding on the top of Said base 5 may be smoothly rotated through any angle and by means of said set screw I6 may be positively locked in any desired position, securely holding said scale arm. I8 in its set position on the workvrsuifa'ce,,-todinsure accuracy-'in marking the laid'out'angle.

It will be seen that a highly efcient, extremely simple layout protractor has been provided which will operate very smoothly and accurately-rand Which is adapted to a Wide variety of layout uses. v

By using a scale arm I8 standing-on1-edgelit is obvious that it Will be a great ldealeasierland more accurate to lay off the desired angles because of the relatively thin upstanding marking edge which extends radially from the rotatable member 'I tofaccurtatelylay offltheang-le indicated on the scale 9. By tighteningcthe: setfscrewt the scale aum; I8 fmaybe lfieldinfanyl desiredposition While the Workis marked. ,This .materially increases the; accuracywof iwits :operatiori;` lThe large ysmooth :bearing surfaces .:on which lthe rotatable member 1 :rides f prevent weXcess wear 'and maintainzaccuracy throughout dong fuse. :By

prividing: .the `grooVe I5; thezsetsscrew I.I-.wli\ll be prevented from. cuttingiintoa :the i bearing. :surface ofthe :spiridlerand: will insuretsrnootlfisoperation. The1simplicityiof the 'construction ofl invention makes Sit economical tto timanufacture :and provides .a 'device uwhich lisvery.".ihafndy to salse, While providing. long-'Wearing parts itoiimaintainza high degree of accuracy of operation for4 aflong period oftime.

'It will `of course 'beiunderstoodfthatryarious changes may A'be made inftheform,:'detai1s, arrangement andproportionsoffthe` parts Without departing from the Ascope-'lof my invention.

'What I claim is: f 1.l '-A layoutprotractor'par'ticularly adaptedfor layingv off angles 'on 1a flat-surface, '.comprisingca stationary member-With an enlargedbaseiportion and a diminished fupstandi-nglspindleportion;:said spindle eportion i having -a peripheral groo've formed therein, a locating'arid:securingipiniex tending? longitud-finally; through lsaid =spiridle zand said 'ibase portion and :adapted to secure .wsai'd member Iat a predeterminedpoi-nt onutheflat-suri face, a rotatable member' journaled on said spindle and riding on said enlarged base portion, a locking and retaining element connected with said rotatable member and adapted to be 5 projected into said groove to retain said rotatable member on said spindle and to selectively hold said rotatable member against rotation on said spindle, means for attaching an arm to said rotatable member Wherebyany desired angle may be laid Aoff, and".v means on zsadllspixidle and rotatablekmember -for indicating theiangle laid off. l2. A layout protractor particularly adapted for =`rlaying off angles on a iiat surface, comprising y -`ifaustiatiorgiary member with an enlarged base portion and a diminished upstanding spindle por- -itionfsaidespiridle portion having a peripheral grooue.-ormed..therein, a locating and securing arid-:aldapted to secure said member at a predetermined point, a rotatable member journaled on saidfspindle andriding onisaid enlargedsbaselportion; afset-screweextending transverselyqthrougli said rotatable member and adapted-ltotberex-Q tendedt-iinto said sgroove ..ftosecure ly hold said rotatable member-against rotation onsaidspi-ndle at any desired point, means for attaching-ian anni to 'said rotatable member whereby -aanydesired anglezfmay :be elaid:ofl; a 36m-degreeangularsscale formed in the topcouterperipheral:rsuraoevoi said .rotatable vrisiefiriber,aand;iarpointer:,securednon said spindle;cooperatingWith/said@angularrscale to; indicate `the langle. laid', off, said-pointereover lapping-the topofssaid:rotatablemexnber,-to,,retain the safmeoonasaiidsspindle.

:REUBEN;H.;:S'IORGH.

fRfEEERENeEstCI'rED "Theifollowing" referencesrareofi recod'iinfithe le o'fithis "patent:

' FOREIGN .PATENTS y Y Number Aififorlntry IDate 251105956 Germanya' ?.'Eeb.:26,:,la9^14 390,875 Germany Feb.'26, 11924 flseoleee :France ?.May mareas Apin extendingthrough said stationary member 

